A pair of equations is shown below: y = 8x − 9
y = 4x − 1

Part A: Explain how you will solve the pair of equations by substitution or elimination. Show all the steps and write the solution.

Part B: If the two equations are graphed, at what point will the lines representing the two equations intersect? Explain your answer.

Suppose that 3% of all athletes are using the endurance-enhancing hormone epo (you should be able to simply compute the percentage of all athletes that are not using epo). for our purposes, a “positive” test result is one that indicates presence of epo in an athlete’s bloodstream. the probability of a positive result, given the presence of epo is .99. the probability of a negative result, when epo is not present, is .90. what is the probability that a randomly selected athlete tests positive for epo? 0.0297